The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Embodiments disclosed herein relate generally to separator. Generally, separators include a class of devices used to separate sized particles, as well as to separate solids from liquids. Separators are used to screen, for example, feed material, fracturing sand, resin coated sand, ceramic proppant, activated carbon, fertilizer, limestone, petroleum coke, roofing granules, salt, sugar, plastic resins, powders, and the like, during industrial sorting and/or manufacturing operations. In petroleum industry applications, separators are often used as components of the drilling fluid processing or circulation system to remove large solids (cuttings) as well as other solids, from the drilling fluid (“mud”).
The separators have been classically divided into rectangular screen separators and circular screen separators. An example of a rectangular screen separator is illustrated in U.S. Pat. No. 6,513,664, and a circular separator is illustrated in U.S. Pat. No. 5,226,546, the disclosures of which are incorporated herein by reference. Each type of separator has its own advantages well known in the industry. A typical separator consists of a box-like, or cylindrical rigid bed, and a screen attached to, and extending across, the bed. The bed is vibrated and/or elliptically moved as the material to be separated is introduced to the screen which moves the relatively large size material along the screen and off the bed and passes the liquid and/or relatively small sized material into a pan or another bed. The bed can be vibrated by pneumatic, hydraulic, or rotary vibrators, in a conventional manner.
Typical circular separators use one or two unbalanced weights mounted far below a frame/screen stack, which has a limit in motion profile range, as well as prevents straight-thru material discharge. Many of these separators have an unbalanced rotating weight on the top and bottom of the vertical motor, and each weight has manual force adjustments and the angle of one weight can be adjusted with respect to the other weight. As a result of the motor/weight location all material discharge spouts must be outside the internal screen diameter. Another limitation of this configuration is the difficulty of managing the vibration profile of tall frame/screen stacks (machine with 3-4 screens in series). With both forces well below the center of mass, generating certain desired motion shapes on the upper screens is not practical. Additionally, it is difficult to adjust the forces and angles or weights on typical separators. Operators must typically remove 1 to 2 guards, lay on the floor, and reach into small spaces to make adjustments to the unbalanced weights. Secondly, once the separator is put back into operation, there is no means to observe the new settings made to the weights, leading to difficulties in verifying process settings for a quality management system.
Shale shakers, which are rectangular separators, are the primary type of separator used on a drill rig. After returning to the surface of the well the used drilling fluid flows directly to the shale shakers where it begins to be processed. Once processed by the shale shakers the drilling fluid may be processed by other equipment and returned to the mud tanks. The solids removed by the shale shaker are discharged from the shaker and conveyed for further treatment or disposal. Shale shakers are a vital component in a solid control system as removing solids, such as drill cuttings, from the fluid permits the drilling fluid to be reused saving cost and reducing waste. However, in addition to the complexity of a shale shaker and its maintenance, it is known in the industry that shale shakers typically have significant mass and require significant space when installed on a drill rig.
Drilling fluids are integral to the drilling process and, among other functions, serve to lubricate and cool the drill bit as well as convey the drilled cuttings away from the bore hole. These fluids are a mixture of various chemicals in a water or oil based solution and can be expensive. For both environmental reasons and to reduce the cost of drilling operations, drilling fluid losses are minimized by separating the fluid from the drilled cuttings so that the drilling fluid properties can be maintained and the drilling fluid may be reused.